1. Field of the Invention
This invention relates generally to receptacles for containing liquids and more particularly to those of the cryogenic type including apparatus for limiting the sloshing of liquid contained therein.
2. Background Description
In cryogenic applications, liquid helium is used as a coolant, and in particular for superconductivity such as in computer technology. Generally, the helium is contained in a reservoir within a vacuum bottle or dewar. In many applications it is desirable to mechanically contain the helium so that it does not slosh around within the reservoir. Sloshing helium causes increased boil-off leading to shorter hold times, and creates temperature fluctuations which are often undesirable.
In magnetic sensing applications, the sloshing heluim creates a magnetic signal due to its slight diamagnetic susceptability. Past attempts to arrest the motions of the helium have involved using plates, tubes and foams as baffles within the reservoir. These attempts are limited as follows: the baffling material displaces liquid helium so that the resulting smaller volume of helium leads to a shorter hold time; in magnetic sensor applications, non-magnetic materials must be used which are quite expensive; and the extremely low viscosity of liquid helium allows the bulk fluid to seek its own gravitational level surface in spite of the presence of the baffling materials.
The foregoing illustrates limitations known to exist in present devices. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.